\section{Predicate  Parser}


\todo{predicate parsing stuff}
  \begin{bluetext}
    a : a x | b (x can be anything)
    =>
    a : b r
    r : x r | e
    -----------------------
    exp : exp op exp | prim
    =>
    exp : prim expR
    expR : op exp expR | e 
  \end{bluetext}



